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Outdoor Exposure Degradation of Ethylene-Vinyl-Acetate Encapsulant Material for Photovoltaic Application

  • K. AgrouiEmail author
  • G. Collins
Chapter
Part of the Engineering Materials book series (ENG.MAT.)

Abstract

Apart from chemical structure, thermal properties of polymers depend mainly on polymer morphology, which is affected by the processing conditions. Outdoor exposure of the materials leads to changes in polymer morphology. The main objective of this experimental investigation was to better understand the changes due to thermal transitions and the molecular organizations of the crosslinked Ethylene-Vinyl-Acetate (EVA) encapsulant material after aging in outdoor exposure. EVA samples are characterized by various thermal and spectroscopic analysis techniques like thermally stimulated current, which is a very sensitive toll to detect polymer degradation. Results show a significant decrease in most properties of EVA in natural field exposure due principally to the specificity of the exposure site. For the aged EVA samples, the distinctive feature of these results is that there are two different endothermic processes due to the recrystallization phenomenon. Furthermore, the difference of the magnitude of peak current by TSC technique suggests increased crosslinking exposure occurring selectively in the high temperature phase as a result of outdoor exposure.

Keywords

EVA encapsulant Photovoltaic module Outdoor aging Thermal analysis 

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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Semiconductors Technology for Energetic Research Center (CRTSE)AlgiersAlgeria
  2. 2.Department of Biomedical EngineeringNew Jersey Institute of TechnologyNewarkUSA

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